Hey guys, been lurking here for a while, anyways I have to machine about 60 12' 1 1/4 sq ss bars. I can only machine 18 inches at a time and the bar is supported on the mill over 22 inches the rest is hung over the machine on roller stands.
Ive been on this project for the last week and a half and finally got down to cutting. Well short progress and were already through a pack of inserts which is equivalent to 10 tools and about three bars done (but have to be rerun to fix the finish). Im pretty sure its my cutter that is causing me grief but wanted to get other opinions before throwing more money away in inserts. Im running a 3/4" 2Fl indexable end mill Im running it at 3005 RPM 107IPM .0625 radial .1875 axial DOC no coolant compressed air at the tool.The chips look good slightly tinted but not blued or burned in anyway. I tried to get some temp readings with the infrared thermometer and I saw a peak of about 200F. Spindle load is 10% on a 30HP spindle. The cut is very loud though like the 2fl isnt the best choice. Im thinking about switching to a 3" face mill that uses the same 90 degree inserts that Im using now 6 of them hoping that the mass and increased flutes will help smooth things out.
Ive attached a picture of the fixture on the machine, it is not complete there are 6 edge clamps that run down the length to clamp the bar. The profile of the bar in the picture is what I have to machine. I put a 3" hole in the wall of the machine to feed the bar thorough and leave the door slightly cracked on the other side. A friend of mine thinks sandbags or something similar on the overhang would help combat the vibration that might develop. Anyone with any advice please chime up, it would be greatly appreciated!